CN108623092A - A kind of method that processing prepares the waste water that para-aminophenol generates - Google Patents
A kind of method that processing prepares the waste water that para-aminophenol generates Download PDFInfo
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- CN108623092A CN108623092A CN201810426562.0A CN201810426562A CN108623092A CN 108623092 A CN108623092 A CN 108623092A CN 201810426562 A CN201810426562 A CN 201810426562A CN 108623092 A CN108623092 A CN 108623092A
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F9/00—Multistage treatment of water, waste water or sewage
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/52—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities
- C02F1/5236—Treatment of water, waste water, or sewage by flocculation or precipitation of suspended impurities using inorganic agents
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/58—Treatment of water, waste water, or sewage by removing specified dissolved compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/66—Treatment of water, waste water, or sewage by neutralisation; pH adjustment
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2103/00—Nature of the water, waste water, sewage or sludge to be treated
- C02F2103/34—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32
- C02F2103/36—Nature of the water, waste water, sewage or sludge to be treated from industrial activities not provided for in groups C02F2103/12 - C02F2103/32 from the manufacture of organic compounds
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- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
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- Environmental & Geological Engineering (AREA)
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- Organic Chemistry (AREA)
- Removal Of Specific Substances (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The present invention relates to a kind of methods that processing prepares the waste water of para-aminophenol generation, i.e., calcium chloride is firstly added in the waste water for preparing para-aminophenol generation, and calcium chloride generates pyrosulfurous acid calcium precipitate with the sodium pyrosulfite in waste water and gets off；After filtering out sediment, strong acid is added, with para-aminophenol at salt；Using the dehydration of the method for distillation or rectifying, the water colorless of abjection contains ethyl alcohol early period, and COD high, and the Sewage treatment set for accounting for the 5%~15% of waste water total amount is used in the preparation process of para-aminophenol, and the waste water that the later stage steams enters biochemical treatment tank and handles.Not only operating procedure is simple for this method, but also avoids Direct Dehydration and have para-aminophenol and take out of, also large-scale industrial production easy to implement.
Description
Technical field
The present invention relates to the technology of wastewater treatment, more particularly to a kind of waste water preparing para-aminophenol generation, i.e., by
P-nitrophenol also original production para-aminophenol when the processing of waste water that generates.
Background technology
Para-aminophenol, alias para hydroxybenzene amine, p-aminophenol, structural formula such as following formula：
Para-aminophenol is the intermediate of the fine chemicals such as medicine, dyestuff, can be used for producing drug acetaminophen, azo
Dyestuff, sulfur dye and developer etc..
The preparation method of the para-aminophenol of document report can be divided into p-nitrophenol reduction according to the difference of synthesis material
Three kinds of method, nitrobenzene reduction rearrangement method and phenol nitrosation reduction method methods, wherein p-nitrophenol reduction method is current industry
Change the method generally used.P-nitrophenol is reduced to para-aminophenol, the method for using the electronations such as iron powder in the past, due to
Mainly hydrogenating reduction that is seriously polluted, using now.
P-nitrophenol hydrogenating reduction is para-aminophenol, and solvent is generally the mixed solvent of second alcohol and water.Reaction terminates
Afterwards, general decrease temperature crystalline is precipitated most of product, and after the most of ethyl alcohol of redistillation abjection, what is left is to contain a small amount of ethyl alcohol and right
Amino-phenol, for COD sometimes up to 100,000 or so, color is the waste water of black, and the amount of waste water is also bigger.And due to amino
Phenol is oxidized easily, in order to not influence the quality of product, so generally after the completion of reaction, being added in the reaction system inorganic
Antioxidant, the most commonly used is sodium pyrosulfites to inhibit para-aminophenol to be aoxidized, so also containing burnt sulfurous in such waste water
Sour sodium.
Such waste water, direct emission will cause huge harm to environment, could be discharged after needing processing.With me
The yield of state's para-aminophenol constantly increases, and the processing of para-aminophenol waste water also just becomes most important.
The general processing method of the organic wastewater of document report has physical absorption or sedimentation, chemical oxidization method and compound
Bacteria microorganism facture.Compound bacteria microorganism treatment cannot handle the waste water of COD high.Physisorphtion, including resin adsorption
Method and active carbon adsorption, presently, there are the problem of to be no adsorbent can reach requirement to the adsorption effect of para-aminophenol,
And there is also link pollution, the higher problems of cost for the processing of the adsorbent after use；Oxidizing process, either dioxygen water oxygen
The shortcomings that change or Ozonation is technological requirement height, especially heavy industrialization device, and cost is also relatively high,
It additionally needs and finds suitable catalyst.
Para-aminophenol waste water is handled there are problem in view of general wastewater treatment method, and the enterprise having at present is using distillation
Or the method for rectifying and dewatering handles para-aminophenol waste water, is handled using the method for simple distillation or rectifying, is steamed greatly in early period
After the ethyl alcohol of part, the water still COD higher that the later stage steams, placing a period of time color in air can deepen, this is because right
Amino-phenol steam forces down, and easily by oxidation blackening；And distillation later stage sodium pyrosulfite decomposes seriously, there is sulfur dioxide production
It is raw.So needing rationally effective wastewater processing technology.
Invention content
It is an object of the invention to overcome the shortcomings of above-mentioned existing para-aminophenol wastewater treatment method, a kind of processing is provided
The new method for preparing the waste water of para-aminophenol generation, thoroughly solves the process problem of para-aminophenol waste water, treated water
Color is colourless, and most COD is less than 3000, can enter biochemical treatment tank.This method is simple for process, is suitable for scale
Industrial production.
The realization of the object of the invention, includes the following steps：
(1) calcium chloride is added in waste water, the sodium pyrosulfite in waste water is generated with calcium chloride under pyrosulfurous acid calcium precipitate
Come, liquid material is obtained after separating sediment.
(2) strong acid is added in liquid material obtained by step (1), is uniformly mixed, makes the para-aminophenol in waste water at salt.
(3) by step (2) processed waste water, distillation or rectifying and dewatering, the COD highers that mid-early stage steams account for waste water
The Sewage treatment set of the 5%~15% of total amount is used in the preparation process of para-aminophenol, and the waste water that the later stage steams can enter life
Change processing pond processing.
The addition of calcium chloride is determined according to the amount containing sodium pyrosulfite in the step (1), calcium chloride and burnt sulfurous
The mole ratio of sour sodium is 1.0:1.0~1.2:1.0, calcium chloride is sufficiently stirred after being added, and is separated by solid-liquid separation after standing sedimentation.
In the step (2) added strong acid be one kind in various concentration sulphuric acids, phosphoric acid, hydrochloric acid, nitric acid and formic acid or
The mixed acid of a variety of acid.
The amount of the amount of added acid is the pH of para-aminophenol waste water after acid adding in the step (2) when being 2~7 acid.
Preferably, the amount of acid added in the step (2) is acid when para-aminophenol wastewater pH is 3~5 after acid adding
Amount.
Advantageous effect：This method prepares the waste water of para-aminophenol generation suitable for processing.Treated, and water color is
Colourless, the high part containing ethyl alcohol is recyclable to be covered in the preparation process for using para-aminophenol, remaining most COD is less than 2000,
Weakly acidic waste water enters biochemical treatment tank processing.This method is simple for process, and industrialized production easy to implement.
Specific implementation method
The application is illustrated and further understood below in conjunction with specific embodiment, but embodiment is only used as example
Son provides, and is not intended as whole technical solutions of the present invention, is not limited overall technical solution.It is all have it is identical or
Similar technique feature, simple change or replacement, belong to the scope of the present invention.
Embodiment 1
At room temperature, take 5L para-aminophenol waste water, COD 98020 that under stirring, 80.00g calcium chloride solids are added, followed by
Continuous stirring 30min, has sediment generation, filters to obtain 61.91g solids.The 50.0mL concentrated sulfuric acids are added in filtrate, stirring makes sulfuric acid
With para-aminophenol fully at salt after, pH value be 4 or so.3 hours are stood at normal temperatures, there is solid precipitation, filters, obtains 43.96g
Solid.
Para-aminophenol waste water filtrate is added and is furnished with 7 centimetres of outer diameter, 3 centimetres of internal diameter, the rectifying of high 30 centimetres of jacketeds
In three mouthfuls of sesame seed cakes of column and the 10L of Rectification head.It is heated with 70 DEG C of hot water by chuck outside rectifying column, Rectification head tap water
It is cooling.Normal pressure steams water, and reflux only has the natural back flow of rectifying column, without exteenal reflux.The water steamed is colourless.Water outlet is divided into 4
Part：First part is discharged 400mL, as clear as crystal, pH value 6, COD 220300；Second part is discharged 300mL, limpid
It is bright, pH value 5-6, COD 2300；Part III is discharged 3600mL, as clear as crystal, pH value 5, COD 906；Part IV
It is discharged 200mL, as clear as crystal, pH value 4-5, COD 1560.After a night is placed in water outlet, Part IV becomes faint yellow, and
It is other not have any color change；It is detected again after 13 days, any variation does not occur for solution colour and pH value.
Embodiment 2
At room temperature, take 5L para-aminophenol waste water, COD 98020 that under stirring, 60.00g calcium chloride solids are added, followed by
Continuous stirring 30min, has sediment generation, filters to obtain 60.00g solids.The 42.0mL concentrated sulfuric acids are added in filtrate, stirring makes sulfuric acid
With para-aminophenol fully at salt after.3 hours are stood at normal temperatures, there is solid precipitation, filters, obtains 41.50g solids.
Para-aminophenol waste water filtrate is added and is furnished with 7 centimetres of outer diameter, 3 centimetres of internal diameter, the rectifying of high 30 centimetres of jacketeds
In three mouthfuls of sesame seed cakes of column and the 10L of Rectification head.It is heated with 70 DEG C of hot water by chuck outside rectifying column, Rectification head tap water
It is cooling.Normal pressure steams water, and reflux only has the natural back flow of rectifying column, without exteenal reflux.The water steamed is colourless.Water outlet is divided into 4
Part：First part is discharged 425mL, as clear as crystal, pH value 4-5, COD 211300；Second part is discharged 545mL, limpid
It is transparent, pH value 4-5, COD 1981；Part III is discharged 3180mL, as clear as crystal, pH value 4-5, COD 898；4th
Part water outlet 260mL, as clear as crystal, pH value 4-5, COD 1620.After a night is placed in water outlet, Part IV becomes yellowish
Color, and other do not have any color change；It is detected again after 13 days, any variation does not occur for solution colour and pH value.
Embodiment 3
At room temperature, take 5L para-aminophenol waste water, COD 782300 that under stirring, 45.00g calcium chloride solids are added, then
Continue to stir 30min, has sediment generation, filter to obtain 52.74g solids.The 60.0mL concentrated sulfuric acids are added in filtrate, stirring makes sulphur
Acid and para-aminophenol fully at salt after.3 hours are stood at normal temperatures, there is solid precipitation, filters, obtains 42.05g solids.
Para-aminophenol waste water filtrate is added and is furnished with 7 centimetres of outer diameter, 3 centimetres of internal diameter, the rectifying of high 30 centimetres of jacketeds
In three mouthfuls of sesame seed cakes of column and the 10L of Rectification head.It is heated with 70 DEG C of hot water by chuck outside rectifying column, Rectification head tap water
It is cooling.Normal pressure steams water, and reflux only has the natural back flow of rectifying column, without exteenal reflux.The water steamed is colourless.Water outlet is divided into 4
Part：First part is discharged 300mL, as clear as crystal, pH value 6, COD 193400；Second part is discharged 350mL, limpid
It is bright, pH value 6, COD 1578；Part III is discharged 3775mL, as clear as crystal, pH value 5-6, COD 875；Part IV
It is discharged 300mL, as clear as crystal, pH value 4-5, COD 2057.After a night is placed in water outlet, there is not any color change.
Embodiment 4
At room temperature, take 5L para-aminophenol waste water, COD 782300 that under stirring, 50.00g calcium chloride solids are added, then
Continue to stir 30min, has sediment generation, filter to obtain 43.15g solids.The 55.0mL concentrated sulfuric acids are added in filtrate, stirring makes sulphur
Acid and para-aminophenol fully at salt after.3 hours are stood at normal temperatures, there is solid precipitation, filters, obtains 40.12g solids.
Para-aminophenol waste water filtrate is added and is furnished with 7 centimetres of outer diameter, 3 centimetres of internal diameter, the rectifying of high 30 centimetres of jacketeds
In three mouthfuls of sesame seed cakes of column and the 10L of Rectification head.It is heated with 70 DEG C of hot water by chuck outside rectifying column, Rectification head tap water
It is cooling.Normal pressure steams water, and reflux only has the natural back flow of rectifying column, without exteenal reflux.The water steamed is colourless.Water outlet is divided into 4
Part：First part is discharged 320mL, as clear as crystal, pH value 6, COD 191200；Second part is discharged 260mL, limpid
It is bright, pH value 5, COD 1627；Part III is discharged 3500mL, as clear as crystal, pH value 5, COD 892；Part IV goes out
Water 300mL, as clear as crystal, pH value 4-5, COD 1320.After water outlet is placed three days, there is not any color change.
Claims (5)
1. a kind of method that processing prepares the waste water of para-aminophenol generation, it is characterised in that steps are as follows for this method：
(1) calcium chloride is added in waste water, the sodium pyrosulfite in waste water generates pyrosulfurous acid calcium precipitate with calcium chloride and gets off, point
Liquid material is obtained after separating out sediment；
(2) strong acid is added in the liquid material that step (1) generates, is uniformly mixed, make para-aminophenol in waste water and acid at
Salt；
(3) by step (2) processed waste water, distillation or rectifying and dewatering, the COD high that mid-early stage steams, waste water total amount is accounted for
5%~15% Sewage treatment set is used in the preparation process of para-aminophenol, and the waste water that the later stage steams enters biochemical treatment tank
Processing.
2. the method that a kind of processing according to claim 1 prepares the waste water of para-aminophenol generation, it is characterised in that institute
The addition for stating calcium chloride in step (1) is determined according to the amount containing sodium pyrosulfite, mole of calcium chloride and sodium pyrosulfite
Amount is than being 1.0:1.0~1.2:1.0.
3. the method that a kind of processing according to claim 1 prepares the waste water of para-aminophenol generation, it is characterised in that institute
State the mixing that acid added in step (2) is one or more acid in various concentration sulphuric acids, phosphoric acid, hydrochloric acid, nitric acid and formic acid
Acid.
4. the method that a kind of processing according to claim 1 prepares the waste water of para-aminophenol generation, it is characterised in that institute
The amount for stating in step (2) added acid be after acid adding para-aminophenol wastewater pH be needed for 2~7 plus amounts.
5. the method that a kind of processing according to claim 4 prepares the waste water of para-aminophenol generation, it is characterised in that institute
The amount for stating institute's acid adding in step (2) be after acid adding para-aminophenol wastewater pH be needed for 3~5 plus amounts.
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112479423A (en) * | 2020-11-18 | 2021-03-12 | 辽东学院 | Wastewater treatment method for producing amino-containing phenolic compounds |
| CN115521014A (en) * | 2022-10-28 | 2022-12-27 | 辽宁世星药化有限公司 | Method for treating wastewater generated in production of p-aminophenol by catalytic hydrogenation of nitrobenzene |
| CN115636522A (en) * | 2022-09-07 | 2023-01-24 | 安徽东至广信农化有限公司 | Integrated treatment process for p-aminophenol production wastewater |
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| CN107117749A (en) * | 2017-05-17 | 2017-09-01 | 浙江奇彩环境科技股份有限公司 | A kind of para-aminophenol produces the recycling processing method of waste water |
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| CN101372381A (en) * | 2008-09-18 | 2009-02-25 | 山东农业大学 | 3,3'-dichlorobenzidine hydrochloride waste water reclaiming method and apparatus thereof |
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|---|---|---|---|---|
| CN112479423A (en) * | 2020-11-18 | 2021-03-12 | 辽东学院 | Wastewater treatment method for producing amino-containing phenolic compounds |
| CN112479423B (en) * | 2020-11-18 | 2022-12-27 | 辽东学院 | Wastewater treatment method for producing amino-containing phenolic compounds |
| CN115636522A (en) * | 2022-09-07 | 2023-01-24 | 安徽东至广信农化有限公司 | Integrated treatment process for p-aminophenol production wastewater |
| CN115521014A (en) * | 2022-10-28 | 2022-12-27 | 辽宁世星药化有限公司 | Method for treating wastewater generated in production of p-aminophenol by catalytic hydrogenation of nitrobenzene |
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